JACKSONVILLE, Fla. -- When 26-year-old Claire Duncan died of a fractured skull after a severe rollover accident in her 2000 Ford Explorer, her family wanted answers.

Their questions about how the SUV's roof caved in led to a lawsuit and ultimately a trial this month that uncovered internal Ford Motor Co. documents and memos that raise serious questions about the Explorer's roof and the automaker's contention that stronger vehicle roofs do not prevent deaths and injuries in rollovers.

On March 18, a Jacksonville, Fla., jury ruled the Explorer's roof was defective and ordered Ford to pay Duncan's husband $10.2 million for economic damages, pain and suffering.

Company documents shown to the jury revealed the Explorer's roof was made weaker when the SUV was redesigned twice in the 1990s -- after engineers recommended strengthening the roof earlier in the decade. Duncan's lawyers also used internal company memos that show Ford's Volvo subsidiary considered roof strength critical to protecting passengers in rollover crashes.

The Explorer's roof exceeds federal safety standards, said Ford spokeswoman Kathleen Vokes, adding that real-world crash data show the Explorer is a safe vehicle, with a comparable fatality rate to similar SUVs. The Explorer was completely redesigned for the 2002 model year, and the current version was not examined during the trial.

Ford plans to appeal the Duncan verdict.

Vokes said Claire Duncan's crash was caused by a reckless RV driver, and her injuries would have been fatal even if the roof had not collapsed.

"Rollover events, real-world crash data and a wide variety of rollover-type testing have been investigated and analyzed for many years," Vokes said. "This work establishes that simply strengthening a roof will not affect the outcome of the crash for the simple reason that injury mechanics are not related to how much the roof is deformed in a rollover crash."

But it was the fourth time in less than 10 months that Ford has lost a jury trial in an Explorer rollover case.

And trial lawyers are heralding the latest evidence as a breakthrough in efforts to implicate Ford in hundreds of rollover deaths.

Ford and other automakers have argued for more than three decades that roof strength is not a factor in rollover deaths and injuries.

Duncan's husband, Scott, said he hired lawyers so he could find out what had happened to Claire and work to prevent similar deaths. He was a passenger in the May 2001 rollover crash.

Claire Duncan, a chemical engineer and graduate student, was driving on I-95 in Virginia and was trying to avoid an RV drifting into her lane.

There was a bump, and she lost control.

The blue Explorer rolled five times before coming to rest. Duncan suffered a fractured skull and died at the hospital shortly after the crash. The roof had crumpled down to the driver's seat.

"The money won't bring my wife back," Scott Duncan said. "What is important is standing up for her and getting them to fix this vehicle. I want people to know how dangerous a vehicle this is."

Capping the Explorer

In April 2004, The Detroit News reported that an estimated 7,000 people are killed or seriously injured each year when their vehicle roofs collapse, according to federal statistics.

The News investigation found that in 1971, Ford and General Motors Corp. led an industrywide effort to convince federal officials to adopt a minimum standard for roof strength -- but only after their vehicle fleets failed the government's first proposed test. Since then, automakers have vigorously fought attempts to upgrade the rule, known as standard 216.

GM, Ford, DaimlerChrysler AG's Chrysler Group and other automakers say the roofs on all their light vehicle models meet federal safety standards, though GM also has been subject to several suits that allege defective roofs led to injury.

But safety experts have long complained standard 216 is too weak to protect passengers in rollovers.

In August, the National Highway Traffic Safety Administration issued new research on roof strength that established a link between roof collapse and injuries. The study showed that the government has a firm scientific basis to require a tougher roof strength regulation. An agency proposal to update the standards has been under review by the White House for several months.

Duncan's lawyers used company documents and crash-test videos to paint a picture of engineers designing down to a minimum federal safety standard while engineers at Volvo, a Ford subsidiary since 1999, took a radically different approach in developing its XC-90 SUV.

Robert Link, one of Duncan's attorneys, said the Explorer had a weaker roof than comparable SUVs like the Chevy Blazer and the Jeep Cherokee, and its roof barely passed federal safety standard 216.

The roof became weaker after the Explorer was redesigned in the 1990s. Ford executives decided each time to put the redesigned SUV on the market even though the roof's strength-to-weight ratio fell below 1.875, the internal safety guideline Ford used for other vehicles, Link said.

In an Oct. 25, 1993, memorandum reviewing the roof strength of the 1995 model year Explorer, Ford engineers J.C. Cheng and Jessy Li expressed concern about how two roof supports, the A-pillar by the windshield and B-pillar between the front and rear seats, performed in a roof-crush test. They recommended reinforcing the middle of the B-pillar, which was "one of the weakest points in this structure." They recommended high-strength steel over cold-rolled steel to make the A-pillar stronger.

But the Explorer's roof didn't get stronger.

In 1995, the Explorer's strength-to-weight ratio was 1.72. In 1999, the number had fallen to 1.56, just over the federal minimum of 1.5. The slim safety margin concerned company engineers, according to internal e-mails from October 1999 that were unsealed at the trial.

"They recognized their strength-to-weight ratio was going down," said Steven Meyer, an automotive safety engineer who testified against Ford during the Duncan trial. "Each time, they had a chance to fix it, and they didn't. They decided to put it into production instead. They made an exception for the Explorer."

Volvo's testing regimen

Ford relied on the static government roof strength test, standard 216, to certify rollover safety before bringing the Explorer to market. In the test, force is applied by a 12-by-72-inch steel plate. If the roof supports 1.5 times the vehicle weight with less than 5 inches of intrusion or crush, it passes.

By contrast, according to test reports and crash videos at the trial, Volvo conducted a battery of dynamic tests designed to more accurately simulate what would happen in a real-life crash before selling the XC-90 SUV.

According to safety experts, the XC-90 has one of the strongest roof structures of any SUV in the industry. To get there, the Swedish automaker went to great lengths to study both the roof strength and the performance of seat belts in its S80 sedan and applied the lessons to its SUV.

One test report -- never before made public -- showed that in August 1999, a Volvo S80 sedan was put on a dolly and accelerated at 30 mph. When the dolly was brought to a sudden halt, the sedan rolled. A video shows that inside, a crash-test dummy received the equivalent of severe head blows as the roof caved in. Volvo engineers also were concerned with the sedan's seat belts, which allowed the dummy to move out of its seat during the roll.

In September 2000, Volvo tested the reconfigured S80 sedan. The dummy's head impacts were deemed minor. The potential for neck injury, deemed "severe" in the first test, was now "minor."

Volvo engineers concluded the stronger roof and improved seat belts had yielded a design that performed better than any previous Volvo model.

"The combination of reinforced roof strength and more effective belt pretensioners were successful!" a Volvo memo stated.

Volvo's internal requirements for crash protection also were made public for the first time. In contrast to Ford's public statements about the irrelevance of roof strength, Volvo's guidelines do not allow for any contact between the dummy's head and the interior structure. Volvo's engineering requirements also prohibit "major loss of structural integrity" and any "failures, separations or collapses."

Volvo's rollover protection requirements also include two crash tests more difficult to pass than federal standard 216 -- a "drop" test and a dolly rollover. With the dolly test, the requirements note, "deformation or failure of interior parts including safety systems that can increase the risk of injury is not allowed."

Ford lawyers challenged these assumptions during the trial. Ford's technical experts said rollover injuries occur by passengers "diving" into the roof before it collapses. They disputed claims that seat belts have improved enough to keep passengers in their seat during a rollover, and said plaintiff's attorneys were oversimplifying complicated engineering issues.

"You are just now getting to the point of having rollover sensors," said Warren Platt, an Orlando lawyer who represented Ford in the Duncan case. "This is not simple science. A stronger roof may have some benefit in some low-energy accidents if it is married to a better belt system. But it's not going to be a silver bullet. There are still going to be rollover deaths."

Raymond Reid, a lawyer for Duncan, said the jury rejected Ford's contention that roof strength is not a crucial factor in rollover crashes.

"If you know you've got a vehicle that has a greater likelihood of being upside down at some point, how do you justify weakening the roof after all these years?" Reid said.

Trial lawyers working on roof-strength cases showed a keen interest in how the Florida jury reacted to the Volvo documents, said Sean Kane, president of Safety Research and Strategies, a Massachusetts legal research firm that served as a consultant on the Duncan case.

"As a corporation, Ford has said roof strength doesn't matter," Kane said. "Yet Volvo is not only saying it does matter, (but also) its tests, which are now public, show it does matter. There's no question this will make it harder for Ford to defend itself in future cases."

As part of the trial, Meyer's engineering firm, Safety Analysis and Forensic Engineering, was hired by Duncan's attorney to conduct a "drop" test to simulate the SUV crash. An equivalent Explorer, suspended on cables upside down and 12 inches off the ground, was dropped onto a concrete floor. The impact speed was estimated at 6 mph. The roof crushed 10 inches.

Another Explorer was modified with structural foam and steel rods inside its hollow roof pillars. The Explorer with the strengthened roof allowed just 3 inches of crush, and it bounced off the ground, rather than flattening.

"I think if Ford had drop-tested one of these Explorers, they would have gotten the same results we did," Meyer said. "The forces that went into that crash were absolutely manageable."

Shifting legal landscape

The Duncan case was the fourth jury verdict against Ford in trials contesting the design of the Explorer's roof in less than 10 months. Previously, Ford had won 13 consecutive Explorer rollover trials.

In June, a California jury awarded a San Diego woman $369 million in damages after a crash in her Explorer left her a quadriplegic. A judge reduced the award to $150 million.

In August, another Florida jury awarded an Explorer victim $5.3 million. On March 1, a trial in Texas resulted in a $31 million verdict against Ford.

Numerous other lawsuits are pending. In an indication of the scope of the problem, Ford lawyers acknowledged there were more than 1,600 lawsuits or claims involving Explorer rollovers before July 2000, when the Duncans purchased their SUV.

Nearly four years after his wife's death, Scott Duncan has gone back to school for a doctoral degree in mechanical engineering. He said the primary ethical requirement of his profession was to protect the health and safety of the public.

"Their argument was she flew into the roof before it collapsed," Duncan said. "As an engineer, that's just ridiculous to me. It's a story they made up to fight litigation."